Medical research has demonstrated the importance of maintaining adequate hydration while engaging in strenuous physical activities, such as running, bicycling, hiking, or mountain climbing. In the not too distant past, participants in such activities carried their water in bottles or canteens from which they drank periodically. More recently, personal hydration systems have been developed that allow users to drink more or less continuously while engaged in sporting or recreational activities. These personal hydration systems typically have a bag-like fluid reservoir that is carried in a back- or waist-mounted pack. A long flexible tube is connected to the reservoir through an exit port at one end and terminates in a mouthpiece at the other end. The tube is long enough to allow the mouthpiece to be carried in the user's mouth to enable the user to draw water from the reservoir at will. Examples of hydration systems and mouthpieces therefore are disclosed in U.S. Pat. Nos. 5,727,714; 5,060,833; 5,085,349; and 6,070,767, the disclosures of which are hereby incorporated by reference.
Athletes have been continuously searching for an edge to compete longer, finish stronger, and remain healthy and competitive. Keeping hydrated has been routinely recognized by athletes as an important contributor to these goals. In fact, during races such as marathons, athletes will often carry liquids (typically water or a drink containing electrolytes, such as Gatorade®, produced by The Gatorade Company, a Delaware Corporation, and a division of PespiCo, Inc.) in addition to consuming liquids provided by the race coordinators. Carrying devices created for runners, however, have many deficiencies when used for other competitive sports where there is physical contact with other athletes or obstacles.